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arXiv · 2512.12665

Variations of two-neutron separation energies and thermal-neutron capture cross sections versus the pairing gap

Hossein Emami·Hadi Sabri
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Abstract

In this work, we investigate the experimental correlation between the pairing gap values and two important observables in the study of nuclear structure (two neutron separation energies and thermal-neutron capture cross-sections). To this aim, we focused on the even-even nuclei in the vicinity of Z=50 and Z = 82 closed proton shells, for which the quantum phase transition phenomena are reported. The results show a significant correlation between the pairing gap and the well-known signatures of quantum phase transitions in the nuclei, which are the candidates for E(5) and X(5) critical points. Also, we have explained the special relation between the pairing gap and the cross-section of thermal neutrons in the considered isotopic chains.

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Hossein Emami, Hadi Sabri. 2025-12-14. Variations of two-neutron separation energies and thermal-neutron capture cross sections versus the pairing gap. https://arxiv.org/abs/2512.12665

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